5 Axis Generic Post

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5 Axis Generic Post5 Axis Generic Post

5-axis post training

Date: October 14, 2002

This presentation is intended as a guide for setting up the

generic 5 axis posts, MPGEN5X_FANUC.PST and

MPGEN5X_MILLPLUS.PST. Run this presentation in

conjunction with a text editing program.


MPGEN5X_FANUC.PST and MPGEN5X_MILLPLUS.PST are generic

5 axis posts that are configurable to these basic machine types:

What are generic 5 axis posts???

Table/Table

Tilt Head/Table

Head/Head

Nutator Table/Table

Nutator Tilt Head/Table

Nutator Head/Head




With these basic machine control types:


Fanuc M (MPGEN5X_FANUC)

Heidenhain MillPlus (MPGEN5X_MILLPLUS)


But this post offers more than positioning data. Some special

features are:


Intelligence is built in to detect rotary limits and automatically

retract and reposition the tool to continue the cut.Define a safety box and the tool moves to it whenrepositioning. A head/head machine configuration followsthe safety box to position around the part.Bias the starting angles at toolchanges and/or on thesecondary axis.

Fan a cut with a rotary axis on the tool to prevent partgouging.

Supports axis substitution and polar conversion.

Limited support for Right/Compound angle head.




MPGEN5X_FANUC.PST and MPGEN5X_MILLPLUS.PST are MP

post processors that have part of the post encrypted using the

MPBIN utility. The encrypted post section is written to a file with

a PSB extension. You should have these files to run the post.

PST File

PSB File

TXT File

These files can be renamed to produce new post processors.

MPBIN has been modified to re-encrypt a PSB file setup to run on

“any SIM”.

The encrypted code is not being released to customers or

dealers.

Required files


Get the Data. What is the axis layout on the machine? Where

are the rotary axis when the machine is at the home position?

How does the machine interpret the rotary data? What are

the rotary axis limits?

Define the part orientation in Mastercam.

Determine which axis is the primary and secondary axis.

Configure the post.

5 Axis Configuration

How do you configure a 5 axis post?




Obtain a picture or drawing with the machine at the home

position. Have the axis address marked on the drawing. Show

the signed axis movement with the limits.

5 Axis ConfigurationGet the Data


How the part is placed relative to the

Mastercam WCS is critical in producing

the proper NC code. Parts are normally

oriented to match the machine zero state.Train your customer to always place the

part drawing or WCS with the orientation

you have determined is needed to

produce proper code.

Nutating machines always have the part

oriented in the top view.


Define the part orientation in Mastercam




The primary axis is the rotary axis

that is rotated first to position a tool

vector in the plane that is

perpendicular to the secondary axis

rotation.

Determine the primary and

secondary axis by imposing the

machine coordinate gnomon onto asimple part drawing in the proper

orientation for the machine.

5 Axis ConfigurationDetermine which axis is the primary and secondary axis

(This step not needed with nutating types)


Observe the axis of rotation for the

machine tool. The Y and Z are the

axis of rotation for this machine.

Select the vectors that represent the

rotary axis. Z+ and Y+ are thosevectors in this example.

Resolve each of these vectors for the

assumed primary axis. Rotate the

vector on the primary axis and

attempt to resolve the vector in the

plane perpendicular to the secondary

axis of rotation. The correct solution

is when both vectors have logical

results.





Assuming the Y axis (B) as the primary axis, resolve by

viewing the vector formed by the Z+ axis by first viewing

down the axis of rotation of the assumed primary axis.

Mentally rotate the vector on the primary axis into the plane

perpendicular to the secondary axis of rotation. View down

the axis of rotation of the assumed secondary axis to

observe the result for the secondary axis. Repeat this for

the Y+ vector. Assume that zero is at 3 o'clock and positive

direction is counterclockwise from the viewing direction.



5 Axis ConfigurationAssuming the Y axis (B) as the primary axis for Z+ vector:

Z+ rotates to B90 on primary Z+ solves to C180 on secondary




5 Axis ConfigurationAssuming the Y axis (B) as the primary axis for Y+ vector:

Y+ is infinite on primary Y+ solves to C90 on secondary



Now re-examine the axis selection assuming the Z axis (C) as the

primary axis. Again, resolve by viewing the vector by first

viewing down the axis of rotation of the assumed primary axis.

Mentally rotate the vector on the primary axis into the plane

perpendicular to the secondary axis of rotation. View down theaxis of rotation of the assumed secondary axis to observe the

result for the secondary axis. Repeat this for the Y+ vector.




5 Axis ConfigurationAssuming the Z axis (C) as the primary axis for Z+ vector:

Z+ is infinite on primary Z+ solves to B90 on secondary


5 Axis ConfigurationAssuming the Z axis (C) as the primary axis for Y+ vector:

Y+ rotates C90 on primary Y+ resolves to B180 on secondary





From the examination where the Yaxis (B) was assumed as theprimary axis; the result of "Y+ isinfinite on primary" and "Y+ solvesto C90 on secondary" is NOTlogical. Therefore, the conclusioncan be drawn that the Z axis is theprimary axis.

Be aware that some trial and error

is often required to make thecorrect selection.


5 Axis Configuration (known cases)

The primary axis is always the rotary axisfixed to the machine tool and thesecondary axis is always the axismounted on the primary axis with the

head/head type machine tools.

The primary axis is always the rotary axis

aligned to the Z axis of the WCS and the

secondary axis is always the nutated axis

with the nutating type machine tools.

See the specific requirements for

configuring the nutating type machine.




The post can now be configured for the machine tool. Thefollowing slides cover the basic settings. Later slides cover themore advanced options and their meaning.

Open the post in the editor of your choice and find these postvariables...

5 Axis ConfigurationConfigure the post


‘mtype’ selects the machine type the post needs to support. The

type is based on where the rotary axis are placed on the machine

tool. This post supports the 6 machine types in the list. Enter the

value corresponding to desired basic machine type.

Post Type Selection

#Machine rotary routine settingsmtype : 0 #Machine type (Define base and rotation planebelow)

#0 = Table/Table#1 = Tilt Head/Table#2 = Head/Head#3 = Nutator Table/Table#4 = Nutator Tilt Head/Table#5 = Nutator Head/Head




Table/Table - type 0

Both rotary axis are located on the machine base and the spindle

remains constant.

Post Type Selection


Tilt Head/Table - type 1

One axis tilts the spindle while the other rotary axis is located on

the machine base.

Post Type Selection




Head/Head - type 2

Both rotary axis are located in the machine head and tilt the

spindle.

Post Type Selection


Nutator Table/Table - type 3

Both rotary axis are located on the machine base and the spindle

remains constant. The rotary axis are not perpendicular.

Post Type Selection




Nutator Tilt Head/Table - type 4

Both rotary axis are located on the machine table and the spindle

remains constant. The rotary axis are not perpendicular.

Post Type Selection


Nutator Head/Head - type 5

Both rotary axis are located in the machine head and tilt the

spindle. The rotary axis are not perpendicular.

Post Type Selection




The primary and secondary axis as selected earlier are used to

setup these plane selections used in the internal math

calculations. The rotary axis is the normal to the plane that we

use with the global variables in the following code.

Define Rotary Axis

#Primary axis angle description (in machine base terms)#With nutating (mtype 3-5) the nutating axis must be the XY planerotaxis1 = vecy #Zerorotdir1 = vecx #Direction

#Secondary axis angle description (in machine base terms)#With nutating (mtype 3-5) the nutating axis and this plane normal#are aligned to calculate the secondary angle

rotaxis2 = vecz #Zerorotdir2 = vecx #Direction


The only valid variables to use with ‘rotaxis1’, ‘rotdir1’, ‘rotaxis2’,

and ‘rotdir2’ are ‘vecx’, ‘vecy’ and ‘vecz’. ‘vecx’, ‘vecy’ and ‘vecz’

can be signed (-vecx for example). The variables correspond to

the gnomon axis designations as shown.

Define Rotary Axis




This is the general relationship of the rotation axis to the plane

selection variables.

Define Rotary Axis


The primary rotation is defined by selecting the gnomon vector

that defines zero (Y+) and assigning it to ‘rotaxis1’. From the zero

vector, select the perpendicular vector in the plane that is the

positive direction of travel (X+) and assign it to ‘rotdir1’.

Define Rotary Axis

rotaxis1 = vecy #Zerorotdir1 = vecx #Direction




The secondary rotation is defined by selecting the gnomon vector

that defines zero (Z+) and assigning it to ‘rotaxis2’. From the zero

vector, select the perpendicular vector in the plane that is the

positive direction of travel (X+) and assign it to ‘rotdir2’.

Define Rotary Axis



The secondary rotation for a nutating axis is defined by the plane

formed by the Z+ vector and the normal to the plane the

secondary (nutated) axis lays in. The assignment implies the

plane the nutated axis is in.

Define Rotary Axis (Nutating)


The nutating axis is in the YZ

plane in this example.




For a nutating axis, the post needs to know the tilt from the Z+

axis. The angle is signed negative if the direction in the plane is

toward X- or Y-.

Define Rotary Axis (Nutating)

#Nutating machine (mtype 3-5) describe the plane that the nutated axis#lays in, this is the plane perpendicular to the primary axis and#secondary axisnut_ang_pri : -45 #Nutating head secondary axis angle from machine Z positive


Often, the setting for the axis signed direction is entered

incorrectly. Setting the direction for table motion is confusing

because the direction the tool vector moves on the part is

opposite of the table direction. Switching the sign is as easy as

changing the sign for the ‘rotdir1’ or ‘rotdir2’ variable.

Rotary Axis Direction Correction

rotaxis1 = vecy #Zerorotdir1 = vecx #Direction

Becomes:rotaxis1 = vecy #Zerorotdir1 = -vecx #Direction




The primary and secondary axis planes must not be the same.

Mathematically this is unacceptable. The following table lists the

acceptable plane combinations.

Rotary Axis Valid Plane Selection

XZXY YZ

YZXYXZ

YZXZXY

Secondary

Option 2

Secondary

Option 1

Primary

Valid Plane Relations


The post variable ‘shift_90_s’ may need to be reversed when the

primary axis zero is not in the plane of the secondary axis and the

secondary axis zero is perpendicular to the primary plane. This is

because the post can select the wrong rotation direction in the

internal calculations. This variable is rarely changed.

Rotary Axis Definition Corrections

shift_90_s : 1 #Shift pos.=1, neg.=-1

Primary Zero

Secondary Zero




The primary and secondary axis can be output with the options

of signed absolute output or implied shortest distance absolute

output within the range of 0 to 360 degrees.

The post always works internally with the angles as if normal

angle output was applied (rotary axis windup in a linear fashion)

and manipulates the angle when writing to the NC file based on

these settings.

Rotary Output Options

pang_output : 0 #Angle output options, primarysang_output : 0 #Angle output options, secondary

#0 = Normal angle output#1 = Signed absolute output, 0 - 360#2 = Implied shortest direction absolute output, 0 - 360


Signed absolute output

Starting at zero (CW positive) -


A-135-135

A270+135

A135+180

A-315-90

A-45-45

A90+90

OutputMotion




Implied shortest distance absolute

Starting at zero (CW positive) -


A135-135

A270+135A135 direction?+180

A315-90

A45-45

A90+90

OutputMotion


The primary and secondary axis address are assigned to the

string variables in this code. ‘str_pri_axis’ is the address for the

primary axis. ‘str_sec_axis’ is the address for the secondary axis.

The post uses the vector math routines with 3D arrays and

‘str_dum_axis’ is a place filler.

Rotary Address

#Assign axis addressstr_pri_axis "C"str_sec_axis "B"str_dum_axis "A"




Rotary limits must be applied to each rotary axis. The range of

the limits, the toolpath and the machine type determines how the

post reacts when a limit is violated. Avoiding the limits is the best

machining practice but this is not always possible. The following

slide is the section from the post where the limits are set. It is

important that the limits are set in degrees and that they are in

terms of normal (unlimited windup) output. Limits are resolved to

these four types:

Less than 180 degrees

Equal or greater than 180 degrees and less than 360 degrees

Soft limit at 0-360 degrees with hard limits slightly beyond

Greater than 360 degrees

Rotary Limits


Rotary Limits

auto_set_lim : 1 #Set the type from the angle limit settings (ignore these)pri_limtyp : 0sec_limtyp : 0

#Rotary axis travel limits, always in terms of normal angle output#Set the absolute angles for axis travel on primary

pri_limlo : -9999pri_limhi : 9999#Set intermediate angle, in limits, for post to reposition machinepri_intlo : -9999pri_inthi : 9999

#Set the absolute angles for axis travel on secondarysec_limlo : -9999sec_limhi : 9999#Set intermediate angle, in limits, for post to reposition machinesec_intlo : -9999sec_inthi : 9999




‘auto_set_lim’ allows the post to examine the limit entries and

automatically set the limit type variables. Leave this enabled.

Rotary Limits

auto_set_lim : 1 #Set the type from the angle limit settings (ignore these)pri_limtyp : 0sec_limtyp : 0


The total rotary axis travel is under 180 degrees. The intermediate

angle is set equal to the axis travel.

Rotary Limit Types

#Set the absolute angles for axis travel on primarypri_limlo : 0

pri_limhi : 110#Set intermediate angle, in limits, for post to reposition machinepri_intlo : 0pri_inthi : 110

Less than 180 degrees




The total rotary axis travel is equal to or over 180 degrees and the

less than 360 degrees. The intermediate angle is set equal to the

axis travel.

Rotary Limit Types

#Set the absolute angles for axis travel on primarypri_limlo : 0pri_limhi : 225#Set intermediate angle, in limits, for post to reposition machinepri_intlo : 0pri_inthi : 225

Equal or greater than 180 degrees and less than 360 degrees


This type, when assigned to the

primary axis, attempts to

reduce the number of limit

retract and approach moves byresetting the limits whenever

the secondary axis is flipped.

Rotary Limit TypesEqual or greater than 180 degrees and less than 360 degrees




The rotary axis travel is normally 360 degrees but the rotary axis

can exceed the travel by a small amount. The intermediate angle

is set at the normal travel and the axis travel is set to the

maximum limits.

Rotary Limit Types

#Set the absolute angles for axis travel on primarypri_limlo : -5pri_limhi : 365#Set intermediate angle, in limits, for post to reposition machinepri_intlo : 0pri_inthi : 360

Soft limit at 0-360 degrees with hard limits slightly beyond


This type uses the

intermediate limit to create a

position to retract and

approach when the nextmove can not be reached

within the repositioned rotary

limits (usually a 360 degree

move).

Prior Move - 45

Post Generated Move - 0

Current Move - 315

Rotary Limit TypesSoft limit at 0-360 degrees with hard limits slightly beyond




The total rotary axis travel is over 360 degrees. The intermediate

angle is set equal to the axis travel. The axis is allowed to

windup. The intermediate angle is set equal to the axis travel.

Rotary Limit Types

#Set the absolute angles for axis travel on primarypri_limlo : -9999pri_limhi : 9999#Set intermediate angle, in limits, for post to reposition machinepri_intlo : -9999pri_inthi : 9999



When a limit is reached with this type rotary limit, the variable

‘typ3_brk_evn’ automatically adjusts the axis travel angles to an

even 360 degree revolution within the travel limits.

Rotary Limit Types

typ3_brk_evn : 0 #Windup limit, use even revolution break position





The variable ‘adj2sec’ stands for “adjust to secondary”. The

purpose of this post switch is to allow the secondary axis limit to

exercise control over the primary axis. By default, the post

attempts to avoid large primary axis moves. When the secondary

limit is tripped, the post attempts to reposition the primary axis.

The primary axis is repositioned with a 180 degree move and the

secondary axis is checked to see if it is within the limits.

Rotary Limit Option

adj2sec : 1 #Attempt to adjust the primary axis from secondary?#Allows primary axis to flip 180 to satisfy secondary#0 = Off #1 = Use method when secondary is out of limit

#Use with pri_limtyp = one to keep secondary as controlling#limit when limit tripped#Use with pri_limtyp = two to allow 180 degree reposition


The rotary axis offset variables hold the distance that the primary

and secondary axis of rotation are offset. They have different

meaning based on the machine type selected. ‘saxisx’, ‘saxisy’

and ‘saxisz’ are used with non-nutating type machine axis offsets

and nutating machine types with the Mill Plus output option and

tool plane toolpaths. ‘n_saxisx’, ‘n_saxisy’ and ‘n_saxisz’ areused with nutating type machine output. The axis offsets are

relative to the machine base matrix (usually the top view).

Rotary Axis Offsets

saxisx : 0 #The axis offset direction?saxisy : 0 #The axis offset direction?saxisz : 0 #The axis offset direction?

n_saxisx : 0 #The axis offset direction?n_saxisy : 0 #The axis offset direction?n_saxisz : 0 #The axis offset direction?




Rotary Axis Offsets – Table/Table


Rotary Axis Offsets – Head/Table




Rotary Axis Offsets – Head/Head


The rotary axis offset for table/table and tilt head/table can have

two interpretations where the program zero point is located

relative to the offset axis. This is a user preference and the

variable must reflect the users preference. The selection is

ignored if the axis have no offset.

Rotary Axis Offsets

r_intersect : 1 #Rotary axis intersect on their center of rotations#Determines if the zero point shifts relative to zero#or rotation with axis offset.

n_r_intrsct : 0 #Rotary axis intersection with nutating (normally zero)




‘r_intersect’ set to 0 directs the

post to calculate output with the

machine coordinate origin at the

part zero (Part/Machine Zero).

The offset distance is from the

Machine Zero to the secondary

axis centerline (Axis Centerline).

The part zero can be set at the

face of the primary axis table.

Rotary Axis Offsets

saxisz : -100 #The axis offset direction?


‘r_intersect’ set to 1 directs

the post to calculate output

with the machine coordinate

origin at the secondary axis

centerline (Machine Zero).

The offset distance is fromthe Machine Zero to the

origin of the part as drawn

(Part Zero). Coordinates are

relative to the Machine Zero

as the secondary axis turns

the part.

Rotary Axis Offsets

saxisz : -100 #The axis offset direction?




The post is capable of breaking large rotary moves into several

smaller rotary moves based on chordal deviation. The variables

‘brk_tol’ (empirical) and ‘brk_tol_m’ (metric) are used when the

fanning routine is enabled. Fanning is normally enabled for

machine types with rotary motion on the spindle and nutating

type machines. Fanning is usually not used with table/table type

machines. See 'brk_mv_head' to enable/disable.

Post Tolerances

brk_tol : .001 #Break up chordal tolerance for 'brk_mv_head'brk_tol_m : .025 #Break up chordal tolerance for 'brk_mv_head', metric

Note: Arc linearization uses the ‘vtol’ and ‘vtol_m’ variables.


Exclusive to this post is a cut location flag. This allows for

spawning events in the post file based on the flags value. The

“retract position” and “plunge point” are generated from the

posts rotary reposition routines.

Post Cut Location Flag

cutflag : one #Path location flag, set in post#Before start - 1#On start - 2#In path - 3#On end - 4#After end - 5#Retract position - 6#Plunge point - 7




The post has the option to convert rapid moves to high feedrate.

Post Feed Options

rot_feed : 0 #Rapid rotary motion only feed options#0 - convert to G0 rapid

#1 - apply rapid feedrate

38. Rapid feedrate? 300.01538. Rapid feedrate (metric)? 10000.0

Rotary moves with no linear motion has the option to be output as

Gcode rapid “G00” or with the high feedrate.

The high feedrate is taken from question 38. or 1538. in the post.

convert_rpd : 0 #Convert rapid to rapid feed


‘use_fr’ selects the feedrate output type. The post only has the

option for unit per minute or inverse feedrate. Degree per minute

is not an option because it is normally not compatible with 5 axis

motion.

Programmed feedrate – Units per minute as programmed in

Mastercam.Inverse feedrate – All feeds are converted to inverse time.

Inverse feedrate on 5 axis continuous – Only 5 axis toolpaths are

output with inverse feedrate.

Inverse feedrate on motion with rotary – Linear moves are output

as unit per minute.

Post Feed Options

use_fr : 2 #Output feedrate#0 - programmed feedrate#1 - inverse feedrate#2 - inverse feedrate on 5 axis continuous#3 - inverse feedrate on motion with rotary




Inverse feed time calculation options allow the post to calculate

the feedrate based on the flute length and to the pivot point on

head/head type machines. The flute length is taken from the

“Flute” entry in the Define Tool dialog from the Mastercam tool

library.

Post Feed Options

inv_fd_typ : 0 #Calculate feed location options#0 - inverse feed at tip#1 - min-max on flute length#2 - tip to pivot on tool length#3 - min-max on flute length to pivot on tool length


Inverse feed at tip – Calculations from tool tip

Min-max on flute length – Calculation from max length on flute

Tip to pivot on tool length - Calculations from tool tip as ratio to

pivot.

Min-max on flute length to pivot on tool length - Calculation from

max length on flute as ratio to pivot.

Post Feed Options




The feedrate can be calculated or passed to the post as zero.

Zero feed calculations often happen when the length between

positions from the NCI file are extremely small. After rounding to

the output format, these moves are coincident. Zero feedrate in

the NC code is a serious problem. To avoid stopping the machine

tool, the following should be set to apply the default feed values

in zero feedrate cases.

Post Feed Options

fix_fr : 1 #If feedrate is zero, apply these valuesdeffeedpm : 1.0 #Default for zero feed in inch/mindeffeedpm_m : 25.0 #Default for zero feed in mm/mindeffrinv : 500.0 #Default for zero feed inverse time


String assignments for the MillPlus control's feedrate axis control

address should be set if enabled. The feedrate axis control

variables are used prior to V410 on the MillPlus control to

calculate rotary feeds and are enabled with the 'radius_fr' switch.

radius_fr : 0 #Use axis radius distance

#Mill Plus, Assign feedrate axis addressstr_pri_f40 "C40="str_sec_f40 "B40="

'mpgen5x_millplus' Post Setting




This is primarily added to handle the nutating machine types but

can also be used with the standard machine types. When

‘top_map’ is active, the toolpaths are output as if a table/table

machine was specified. Code must be added to the post to

handle the machine specific mapping routine. Other post

variables must be set for this output. The following slides are a

guide to these additional variables.

'top_map' Post Settings

top_map : 1 #Output toolplane toolpaths mapped to top view


'top_map' actually switches machine type based on 5 axis

continuous toolpaths or toolplane positioning toolpaths. To

restore the original machine setting, the postblock below is

embedded in the initialization section of the post. Replace the

second argument in the formulas with the global assignments for

‘rotaxis1’, ‘rotdir1’, ‘rotaxis2’ and ‘rotdir2’.

rotaxis1 = vecy #Zerorotdir1 = vecx #Directionrotaxis2 = vecz #Zerorotdir2 = vecx #Direction

#NOTE: Use of 'top_map' requires the dealer match the# above settings below. These must match initial settings!!!p_nut_restore #Postblock, restores original axis settings

result = updgbl(rotaxis1, vecy) #Zeroresult = updgbl(rotdir1, vecx) #Directionresult = updgbl(rotaxis2, vecz) #Zeroresult = updgbl(rotdir2, vecx) #Direction





The toolplane angle position address is used with the 'top_map'

command for toolplane positioning and mapping on the control.

See the next slide for toolplane rotation angle selections.

#Toolplane mapped to top angle position stringsstr_n_a_axis "A5="str_n_b_axis "B5="str_n_c_axis "C5="



Switching to toolplane positioning toolpaths with 'top_map'

requires that a selection be made for the rotary axis to be used.

Make a selection from the options presented.

top_type : 3 #With 'top_map' select toolplane output#0 = Post selects map rotation axis

#1 to 4, user selected map rotation axis#1 = Primary C : X zero, Secondary B#2 = Primary C : Y zero, Secondary A#3 = Primary C : -X zero, Secondary B#4 = Primary C : -Y zero, Secondary A





Tool length is most often used with post types - Tilt Head/Table or

Head/Head. How the tool length is obtained can be selected with

the variable ‘use_tlength’. Enter 0 to use the value entered in the

variable ‘toollength’ (See code below). Initialize to 1 and the

length is taken from the “Overall” entry in the Define Tool dialog

from the Mastercam tool library. Set to 2 prompts the user for the

tool length at each tool change when the post is run.

Post Tool Length

use_tlength : 0 #Use tool length, read from tool overall length#0=Use 'toollength' var, 1=Mastercam OAL, 2=Prompt

toollength : 0 #Tool length if not read from overall length


The tool length with Head/Head machine types can be applied to

the output positions. The options are 0 to add the tool length in

the current tool direction to the output, 1 to add the tool length as

in option 0 and then subtract the length from the Z axis. Enter 2

and the tool length is not added (tool tip programming) but we

have the length for feed and fanning calculations.

Post Tool Length

shift_z_pvt : 0 #Shift Z by tool length, head/head program to pivot (Z axis only)#0=Pivot, 1=Pivot-Z, 2=Tool Tip Programming (without zero length)#Option 2, So we can still take advantage of brk_mv_head feature




Post Tool LengthOption 0 is used when the tool tip is the zero pick up position.

Option 1 is used when the tool pivot is the zero pick up position.


‘add_tl_to_lim’ stands for “add tool length to limits”. The limits

referred to are the linear limits enabled with the variable

‘use_stck_typ’. This controls if the limits are considered absolute

when retracting for repositioning.

Post Tool Length

add_tl_to_lim : 0 #Add tool length after intersecting limit, always#on if limit from stock




Linear stock limits are used by the post during approach and

retract from the part and during a rotary axis reposition triggered

by a rotary axis limit violation. These do not trigger a warning

when violated, they are intended as a safety zone the same as

those defined in Mastercam.

Post Linear Limits

use_stck_typ : 0 #0=Off, 1=Stock def., 2=Limitsup_x_lin_lim : 500.0 #X axis limit in positive directionup_y_lin_lim : 500.0 #Y axis limit in positive directionup_z_lin_lim : 500.0 #Z axis limit in positive directionlw_x_lin_lim : -500.0 #X axis limit in negative directionlw_y_lin_lim : -500.0 #Y axis limit in negative directionlw_z_lin_lim : -100.0 #Z axis limit in negative direction

‘use_stck_typ’ uses the values from job setup to fill the limit

variables when set to 1. When set to 2, the values are used as

they are set in the post.


How do the linear stock limits work? The limits are used to create

a box. This box is then intersected by the tool vector for the

retract move and the tool vector for the approach move. The

vectors are adjusted for the machine type and moves are

generated to follow the extents of the box to reposition the tool.

Post Linear Limits




‘clear_stck’ is used to modify the linear stock limits. This is used

when using the stock size from Job Setup to add an additional

clearance to the stock size.

Post Linear Limits

clear_stck : 0.0 #Add inc. offset to stock definition for transition boundary


This variable allows the post to retract and reposition the tool on

rapid motion from the NCI file. Normally this is enabled. It would

be disabled when the user is making all retracts and approach

moves in the tool path at rapid traverse. Feed moves are not

expected to be part of a retract or approach by the post.

Rotary Limit Option

retract_on_rpd : 1 #This control allows retract on rapids too (don'tassume rapid is safe)




The variable 'use_clamp' adds the rotary axis clamp Mcodes to

the NC output. These are applied with toolplane positioning and

drill cycles. 5 axis tool paths can not have the rotary axis

clamped because rotary motion is expected.

Post Clamp Option

use_clamp : 0 #Use the automatic clamp Mcode

Find this section in the post to change the strings for the clamp

code.

# Primary axis lock/unlockspunlock M79 # Unlock Rotary Tablesplock M78 # Lock Rotary Table

# Secondary axis lock/unlockssunlock M11 # Unlock Rotary Tablesslock M10 # Lock Rotary Table


The machine base option allows the NCI input to be mapped to a

different coordinate system in the NC output. Alter the matrix

settings to a view that is the target output. This is helpful for

machines with left hand coordinate systems or horizontal

machines where the user prefers a setup relative to the machine

tool.

Post Machine Base Option

#Machine base matrix (Base matrix to map positions into)matb1 : 1matb2 : 0matb3 : 0matb4 : 0matb5 : 1matb6 : 0matb7 : 0matb8 : 0matb9 : 1




This example shows a horizontal machine setup where the user

prefers a setup relative to the front view in Mastercam. The user

can now program the tool paths with the part relative to the

machine zero (as shown below). The post configuration settings

are relative to this matrix.

Post Machine Base Option

matb1 : 1matb2 : 0matb3 : 0matb4 : 0matb5 : 0matb6 : 1matb7 : 0matb8 : -1matb9 : 0


The rotary limit tolerances are used in the post to trigger the

revolution counter, find large rotary moves to flip the secondary

axis and determine when limits have been violated requiring

repositioning. Normally, these values do not need adjustment.

The following slides give a more detailed description of each

variable.

As a general rule, large changes in the tool vector directions

should be avoided with 5 axis tool paths to avoid unexpected

repositioning.

Post Rotary Limit Tolerances




The tolerance settings for wind up determines at what point to

add or subtract from the internal revolution counter. The

comparison is to the raw angle calculations which are in the

range of 0 to 360 degrees. The design is to prevent moves

exceeding this threshold.


#Tolerance settings for wind upp_tol_ang : 210 #Primary angle move to exceed for direction changes_tol_ang : 210 #Secondary angle move to exceed for direction changed_tol_ang : 210 #Dummy angle move to exceed for direction change


'p_rsoft_tol' is the primary angle change in degrees to exceed to

trip for tool reposition or adjustment to the secondary axis. For

'rotary limits less than 180 degrees', 'equal or greater than 180

degrees and less than 360 degrees' and 'soft limit at 0-360

degrees' any rotary move exceeding the value makes a call to the

routines to check for limit violations or adjustment to thesecondary axis.


#pri_limtyp = 1, tolerance to validate tripping limit# reset the p_frc_adj_sec flag when back to normal range#pri_limtyp = 2, angle move >= to trigger reposition on primary and# angle move >= with rev5 or 180 reposition to validate tripping limitp_rsoft_tol : 45




The variable 's_soft_tol' is the secondary angle change in degrees

to exceed to trip a tool reposition. This tolerance is only used

with soft limit at 0-360 degrees on the secondary axis.


#sec_limtyp = 2, Angle move >= for repositions_soft_tol : 270


After a limit has been tripped by either a limit or a large rotary

move, the post attempts to adjust the move within an acceptable

range. If the recalculated rotary move is below the degree value

in 'adj_lim_trp', the limit trip indicators are set off and the

repositioning routine is not called.


adj_lim_trp : 90 #Angle move in p_pri_rot180 to trip reposition




'p_rsoft_tol3' is the primary angle change in degrees to exceed to

trip for tool reposition or adjustment to the secondary axis. For

'greater than 360 degrees' any rotary move exceeding the value

makes a call to the routines to check for limit violations or

adjustment to the secondary axis.


#pri_limtyp = 3 and sec_limtyp = 3 control valuesp_rsoft_tol3 : 90 #Angle move >= with rev5 or 180 reposition


The post relies on the miscellaneous reals and integers to

interpret the users intent and control the rotary axis. These are

also used to provide additional functionality.

A major problem for any post is understanding what occurred

through a null toolchange or a retract and approach from one

chain to another. The post can not see if adequate clearance from

the part was programmed in the toolpath or if a collision could

occur by calling the routines to retract and approach in the post.

The post can not determine the optimum starting angles for the

rotary axis to avoid tripping a limit. All these and more can be

controlled with the miscellaneous reals and integers.

Miscellaneous Reals/Integers




Select absolute or incremental positioning output. Toolchange

positioning is always in absolute mode.

Miscellaneous Integers# mi2 - Absolute or Incremental positioning at top level# 0 = absolute# 1 = incremental

G0 G54 G90 X .5676 Y7.4665 C182.81 B 25.671 S2139 M3

G43 H1 Z.8198 M8

G1 X .3588 Y7.4842 Z.7483 C181.73 B 24.288 F6.42

X .1316 Y7.4968 Z.6799 C180.525 B 22.913

G0 G54 G90 X .5676 Y7.4665 C182.81 B 25.671 S2139 M3

G43 H1 Z.8198 M8

G1 G91 X.2088 Y.0177 Z .0715 C 1.08 B1.383 F6.42

X.2272 Y.0126 Z .0684 C 1.205 B1.375

mi2 = 0:

mi2 = 1:


mi3 selects the reference return position. mpgen5x_millplus uses

G74 and the entries in mr3, mr4 and mr5.

Miscellaneous Integers# mi3 - Select G28 or G30 reference point return.# 0 = G28, 1 = G30




A bias is a request to the post to attempt to start the machine

position close to the entered value. The actual value output to the

post is a result of the internal calculations. 999 and -999 are

interpreted as a command to position as close to the limits set in

'pri_limlo' and 'pri_limhi'. 0 indicates that the calculations should

occur without attempting any bias.

Miscellaneous Integers# mi4 - Start initial primary rotary axis bias# +/-999 represents start as close to limit as possible# 0 represents calculate without using bias# Any other value represents an angle in degrees to attempt# to position near.# -999 = Low, 0 = Off/Default, 999 = Hi, Value = Angle bias


The secondary bias functions the same as the primary biasexcept it is subordinate to the primary axis in cases of conflict.

999 and -999 are interpreted as a command to position as close to

the limits set in 'sec_limlo' and 'sec_limhi'. 0 indicates that the

calculations should occur without attempting any bias.

Miscellaneous Integers# mi5 - Start initial secondary rotary axis bias# +/-999 represents start as # close to limit as possible# 0 represents calculate without using bias# Any other value represents an angle in degrees to attempt# to position near.# -999 = Low, 0 = Off/Default, 999 = Hi, Value = Angle bias




The bias settings are used to control the initial rotary axis

positions at the start of file or a toolchange. Depending on the

machine rotary limits, the user may need to edit 'mi4' and 'mi5'

after posting to remove retracts and approaches because of the

initial rotary calculations. The post does not have logic to look

ahead in the toolpath to determine the optimal start angles. The

'bias_null' variable allows the post to use 'mi4' and 'mi5' to adjust

the angle through a null toolchange (no change in tool number).

Miscellaneous Integers

bias_null : 1 #mi4 and mi5 bias are applied at null toolchanges


Depending on the type of toolpath (5 axis motion or toolplane

positioning), the user may want to select a different work origin

on the machine tool. The part origin must remain a constant with5 axis motion. With toolplane positioning the user may select a

different origin location and enter the work offset in the control

register. mi6 shifts the output coordinates to the origin selected

in Mastercam for toolplane positioning. 5 axis toolpaths are

always output relative to the Mastercam WCS origin.

Miscellaneous Integers# mi6 - Add work shift position for rotation center programming# 0 = Output relative to work origin (toolplane)# 1 = Output relative to WCS origin (axis shifts)




mi7 disables the post generated retract and approach from the

part. The moves should be disabled when the user has made

moves in the toolpath to clear the part at a rotary reposition or an

obstacle is present where the retract is occurring. The rotary axis

moves required to stay in the rotary limits are generated.

Miscellaneous Integers# mi7 - Enable retract to and from linear limits. Disable for# internal work to prevent part collisions.# 0 = Disable, 1 = Enable


mi8 controls when the retract and approach are used relative to

the toolpath toolchanges and 5 axis chains. This is needed

because the post does not know if the user has made the retract

and approach part of the toolpath at toolchanges and the

beginning and end of 5 axis chains with multiple cuts.

Miscellaneous Integers# mi8 - Safe retract/approach at toolchange.# The tool retracts/approachs to limits from last path to current# path or after/before a toolchange# (limits must be enabled, see 'use_stck_typ')# 0 = Disable all toolchange retract/approach# 1 = Enable null toolchange retract/approach only

# 2 = Enable toolchange retract/approach only# 3 = Enable both toolchange retract/approach# 4 = Enable retract/approach between 5 axis chains (cutpos) in# toolpath or sign 1 to 3 negative with toolchange options




The calculations for the nutating machine types can be controlled

by selecting the linear axis direction that is normal to the plane of

the nutated axis. This should be set to avoid erratic rotary axis

moves in the toolpath.

Miscellaneous Integers# mi9 - Nutating bias calculation.# 0 = Calculate angle bias to original vector# 1 = Bias to positive# 2 = Bias to negative


The secondary axis for the non-nutating machine types can be

controlled by mi10. This value is normally used with head/headtype machines where the secondary axis rotary limits are under

360 degrees. The post controls the travel by temporarily setting

the appropriate limit to 0.

Miscellaneous Integers# mi10 - Secondary axis control (non-nutating)# 0 = Continuous secondary (primary controlled)# 1 = Always stay positive# 2 = Always stay negative




This value is an incremental distance applied to the retract and

approach with the post reposition routine. The retract is at rapid

and the approach is at the plunge feedrate.

Miscellaneous Reals# mr1 - Retract/approach clearance distance at tool reposition


mr2 "rotates" the toolpath on the secondary axis by the entered

value. Any value can be entered but the machine must be setupwith the direction of the tool in the head so it is in the plane

perpendicular to the secondary axis.

Miscellaneous Reals# mr2 - Right angle head toolpath conversion (not with nutating machine).# Right angle rotates secondary axis by degrees# The head may only be rotated perpendicular to the secondary axis# 0 = Off, Enter angle for amount of head rotation (RA = +/- 90)




mr2 applies the tool length along the direction of the tool. This is

the total distance from the intersection of the tool axis and the

spindle axis to the tool tip. mr10 is used for the length along the

spindle axis. This is temporarily applied to the axis shift 'saxisz'.

Miscellaneous Reals


mpgen5x_fanuc for Fanuc controls and table/table configuration

can be setup to use the offset registers on the machine control. It

is not necessary to offset the toolpath (use a tool length or mr10)

when using the control registers. Enable the registers with the

following variables. The offset for the length is stored in the H

register and the shift value is stored in the D register on themachine.

Miscellaneous Reals

use_g45 : 1 #Use G45 offset with right angle head (RA)g45_of_add : 30 #Add this number to tool length no. for G45 offset number

T1 M6

G0 G54 G90 Y .25 C0. B 90. S2139 M3

G45 D31 X.25

G43 H1 Z 1.375 M8

X.1

G1 X0. F6.42




Enter the value to be output with the MillPlus G74 home position

in the mpgen5x_millplus post.

'mpgen5x_millplus' Miscellaneous Reals# mr3 - Mill Plus G74 toolchange X axis home position# mr4 - Mill Plus G74 toolchange Y axis home position# mr5 - Mill Plus G74 toolchange Z axis home position


In addition to the automatic retract and approach, the user may

specify a safe Z level for rotary reposition and toolchanges. The

procedure is ignored when the value is zero. This value is not

checked against the linear limits. Note that the stock limits can

be ignored even though they must be enabled for this option

Miscellaneous Reals# mr6 - Absolute Safe height in Z for unwinds and toolchanges# (limits must be enabled and mi8, see 'use_stck_typ')# (set the limits to zero to ignore limits and use this safe height)# 0 = Off




The axis shift variables can be modified through the

miscellaneous reals as shown. These must be enabled by the

post switch shown below.

Miscellaneous Reals# mr7 - Axis shift for X axis, See 'shft_misc_r'## mr8 - Axis shift for Y axis, See 'shft_misc_r'## mr9 - Axis shift for Z axis, See 'shft_misc_r'

shft_misc_r : 0 #Read the axis shifts from the misc. reals


mr10 serves double duty to provide entry for incremental shift

from the nutating machine Z offset to the table face.

This accommodates for the distance from the part zero location to

the table offset location.For Right Angle head support with non-nutating machine types,

the value is used for the length along the machine spindle.

Miscellaneous Reals# mr10 - Nutating distance from work coordinate zero to table zero (Z axis)# Non-nutating Z axis shift with RA (See mr2)






Header information can be placed in the postblock 'pheader'. The

post was written with the header information in the postblock

'psof'.

pheader #Call before start of file

##### Custom changes allowed below #####

##### Stop custom changes #####

psof #Start of file for non-zero tool number


Header Output

Postblock Customization


This post has been designed to use one common postblock for

toolchange output. This is called for both SOF and toolchanges.

p_goto_strt_tl #Make the tool start up at toolchangepfd_shft_inc

psign_ang_out


Toolchange Output

Regular toolchanges call 'ptlchg' prior to the call to 'p_goto_strt_tl'.

ptlchg #Tool change


pbld, n, "M01", e





Null toolchange output occurs in 'ptlchg0' and 'p_goto_strt_ntl'

postblocks. The calls to the postblocks are in this order.

ptlchg0 #Call from NCI null tool change (tool number repeats)


p_goto_strt_ntl #Make the tool start up at null toolchange

Null Toolchange Output



The post uses a common postblock for the end of a tool path and the

end of the file output.

pretract #End of tool path, toolchange

pretract_movsav_absinc = absinccoolant = zero

End of Tool Output

The end of file postblock, 'peof', is called to write the NC code for

the program end. This postblock calls 'pretract'.

peof #End of file for non-zero tooltoolchng = one!gcode #to see that this is the EOF in pretractpretract





The postblocks for motion output are grouped starting with

'prapidout'. The variables may be reordered but 'xout', 'yout', 'zout',

'p_out' and 's_out' should be used for positioning output. These

variables output absolute or incremental based on the 'absinc'

variable.

prapidout #Output to NC of linear movement - rapid

plinout #Output to NC of linear movement - feed

pcirout #Output to NC of circular interpolation

Motion Output



These postblocks are for specific motion output. 'ppos_cax_lin' is

called for toolplane toolpaths with rotary positioning. It's purpose is

to output the rotary moves before the linear axis motion.

'p_safe_z' is called when the miscellaneous real 6 (mr6) has been setto a non-zero value and the routine enabled by setting mi8 and

'use_stck_typ' on. The call to 'p_goto_pos' calls back to 'pncoutput'

to call the motion output.

ppos_cax_lin #Position the rotary axis before move - rapid

p_safe_z #Safe Z retract move with reposition, see mr6if safe_z_ret,[gcode = zeroza = safe_z_retp_goto_pos]

Motion Output, Special Routines





The postblocks for canned drill cycles output are grouped starting

with 'pdrlcommonb'.

pdrlcommonb #Canned Drill Cycle common call, before..

pdrill #Canned Drill Cyclepdrlcommonb

Canned Drill Cycles Output



The postblocks for canned text output are grouped starting with

'pcan'.

pcan #Canned text - before output call

pcan1 #Canned text - with move

pcan2 #Canned text - after output call

pcant_out #Canned text - build the string for output

Canned Text Output





Postblocks have been provided to afford some control over the post

calculations. These are exposed to allow some flexibility with out

having to make custom PSB files.

plin0 pfd_shft_ovrd #Overide prior to shift and feed calculationif cutflag = 7,[!fr_posfr_pos = plunge_feed]

ppln_mtch_ovrd #Overide plane match, can drill is off if planes don't matchif plane_no = zero,[

Post Overrides



Strings for error messages can be changed for language conversion.

Find this section in the post.

Post Error Messages

# --------------------------------------------------------------------------# Error messages

# --------------------------------------------------------------------------#One time message#Calculationscalcerr "ERROR-POST CALCULATION ERROR"scalcerr1 "ERROR-PRIMARY AND SECONDARY PLANES ARE COINCIDENT"scalcerr2 "ERROR-SPINDLE CAN NOT BE ALIGNED TO AXIS, SEE 'spind_align'"scalcerr3 "ERROR-SETUP FOR PRIMARY OR SECONDARY AXIS IS ILLEGAL"sratioerr "ERROR-THE CALCULATED BREAK IS OUTSIDE THE MOVES"

Post Error Messages




The following slides present some typical machine types and the

basic settings required in MPGEN5X.

Typical Machine Types

Our thanks to Glenn Stephens of CAD/CAM Consulting Services

for allowing us to use his documentation.


Rotary Table on Trunion Table






Rotary Table on Trunion Table (Fadal)pang_output : 1 #Angle output options, primary

sang_output : 1 #Angle output options, secondary

str_pri_axis "A"str_sec_axis "A"

str_dum_axis "C"

mtype : 0 #Machine type (Define base and rotation plane below)

rotaxis1 = vecz #Zero

rotdir1 = vecy #Direction


rotdir2 = -vecx #Direction

pri_limlo : -9999

pri_limhi : 9999

pri_intlo : -9999

pri_inthi : 9999

sec_limlo : 0

sec_limhi : 110

sec_intlo : 0sec_inthi : 90


Tilting Head on Tilting Head




Tilting Head on Tilting Headpang_output : 0 #Angle output options, primary


str_pri_axis "B"str_sec_axis "A"

str_dum_axis "C"



rotdir1 = vecx #Direction


rotdir2 = -vecy #Direction

use_tlength : 1 #Use tool length, read from tool overall length


shift_z_pvt : 1 #Shift Z by tool length, head/head program to pivot (Z axis only)

pri_limlo : -120

pri_limhi : 120

pri_intlo : -120

pri_inthi : 120sec_limlo : -90

sec_limhi : 30

sec_intlo : -90

sec_inthi : 30


Tilting Head on Tilting Head (Gantry)




Tilting Head on Tilting Head (Gantry)pang_output : 0 #Angle output options, primary


str_pri_axis "C"str_sec_axis "A"

str_dum_axis "B"


rotaxis1 = -vecy #Zero



rotdir2 = -vecy #Direction




pri_limlo : -5

pri_limhi : 365

pri_intlo : 0


sec_limhi : 135

sec_intlo : -135

sec_inthi : 135


Rotary Table/Tilting Head




Rotary Table/Tilting Headpang_output : 0 #Angle output options, primary


str_pri_axis "A"str_sec_axis "B"

str_dum_axis "C"




rotaxis2 = -vecx #Zero

rotdir2 = vecz #Direction

pri_limlo : -9999

pri_limhi : 9999

pri_intlo : -9999

pri_inthi : 9999

sec_limlo : -5

sec_limhi : 180

sec_intlo : 0sec_inthi : 180


Rotary Table/Tilting Head (Cincinnati)




Rotary Table/Tilting Head (Cincinnati)pang_output : 0 #Angle output options, primary


str_pri_axis "B"str_sec_axis "A"

str_dum_axis "C"









pri_limlo : -9999

pri_limhi : 9999

pri_intlo : -9999


sec_limhi : 120

sec_intlo : -30

sec_inthi : 120


Rotary Table on Rotary Table (Nutating)




Rotary Table/Rotary Table (Nutating)

top_map : 0 #Output toolplane toolpaths mapped to top view

str_pri_axis "C"

str_sec_axis "B"

str_dum_axis "A"

str_n_a_axis "A5="

str_n_b_axis "B5="

str_n_c_axis "C5="


rotaxis1 = vecy #Zero




p_nut_restore #Postblock, restores original axis settings

result = updgbl(rotaxis1, vecy) #Zeroresult = updgbl(rotdir1, vecx) #Direction

result = updgbl(rotaxis2, vecz) #Zero

result = updgbl(rotdir2, vecx) #Direction

Note: These setting reflect a Deckel Maho Gildemeister machine

tool with the ISO MillPlus control. The 'mpgen5x_millplus' generic

5 axis post should be modified in this case.


Rotary Table/Rotary Table (Nutating)nut_ang_pri : -45 #Nutating head secondary axis angle from machine Z positive

saxisx : 0 #The axis offset direction?

saxisy : 0 #The axis offset direction?

saxisz : 0 #The axis offset direction?

n_saxisx : 0 #The axis offset direction?

n_saxisy : 0 #The axis offset direction?

n_saxisz : 6.1027 #The axis offset direction?

top_type : 3 #With 'top_map' select the top toolplane output

pri_limlo : -9999

pri_limhi : 9999

pri_intlo : -9999

pri_inthi : 9999

sec_limlo : -9999

sec_limhi : 9999

sec_intlo : -9999

sec_inthi : 9999



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